Physical Oceanography Study Guide

abyssal plain: A flat region of deep ocean basins.

ocean ridge: A long, continuous mountain range on the seafloor. Ocean ridges are often of volcanic origin at a point or line of separation in the earth's crust.

Atoll: A ring-shaped coral reef surrounding a lagoon. It may have low sand islands. Atolls rest on submerged volcanic islands

ocean trench: A deep cut or trench in the seafloor, usually close to where continental shelves and seafloors meet.

brackish water: A mixture of fresh and saline (salt) water

Pycnocline: The change in density with depth; encompasses both the thermocline and the halocline

briny water: Water with a high-concentration of salt

Reef: A shallow rock or coral formation often exposed at low tide.

continental shelf: The land forming the shallow seafloor extending outward from the edge of a continent

Salinity: Amount of dissolved salts present in water (Measured in ppt, A.K.A parts per thousand)

continental slope: The sloping front of a continental shelf; the place where the continent ends; like the cliff/dropoff

sea ice: Frozen ocean water

convection currents: Currents made by the rising of warm water and the sinking of cold water

Seamount: An isolated undersea hill or mountain.

current: A body of water or air moving in a definite direction

spring tide: Tides that occur when the moon is full and aligned with the sun

deep current: Currents that occur deep within the ocean; caused by differences in density or temperature

storm surge: Occurs when strong winds caused by storms

density (in relation to currents and ocean water): How compact water’s molecules are together

surface current: Ocean water moves in predictable ways along the ocean surface due to winds

ebb tide/current: When water flows away from the shore; the period of time between high tide and low tide

temperature (in relation to currents and ocean water): Refers to the measurement of how warm or cold ocean water is; temperature plays a crucial role as a primary factor for driving the movement of water/currents

Estuary: A river mouth or channel, or the drowned seaward end of a valley where fresh water from land mixes with seawater

Thermocline: the transition layer between warmer water at the surface and cooler deep water

flood tide/current: When water flows towards the shore; the period of time between low tide and high tide 

thermohaline circulation: Cold salty water in polar regions sinks, pulling in surface water that becomes cold and salty, driving deep water toward the surface.

global conveyor belt: The constantly moving system of deep-ocean circulation driven by temperature and salinity that moves water around the globe

tidal waves: Large tides caused by underwater earthquakes, volcanic eruptions, etc.

Gyre: A major spiral of ocean-circulating currents; circular patterns of surface currents in the world's oceans

Tides: Ocean waves caused by the gravitational pull between the Sun, Moon, and the Earth

Halocline: The change in salinity that creates a density barrier that prevents mixing between surface water and deeper water

Tsunamis: A series of waves generated by a large and sudden displacement of ocean water; most are caused by underwater earthquakes, but they can also be caused by landslides, volcanos, etc.

Lagoon: A shallow body of quiet water almost completely cut off from the open ocean by coral reefs, barrier islands, or barrier beaches.

Upwelling: When cold, nutrient-rich water from moves toward the surface

neap tide: Tides that occur when the moon is in its 1st and 3rd quarters

Waves: Rhythmic disturbances on the ocean's surface.

ocean basin: A large depression in the earth's crust that holds the water of an ocean.

wind-driven waves: Waves created by as wind blows across the surface of the ocean; also known as surface waves